June 19th, 2016

Back in 2010 & 2011 I conducted several studies to detect underrepresented regions a.k.a. “unmapped” places in OpenStreetMap (OSM). More than five years later, some people asked if I could rerun the analysis. Based on the latest OSM planet dump file and Taginfo, almost 1 million places have been tagged as villages. Furthermore, around 59 million streets have a residential, unclassified or service highway value. My algorithm to find unmapped places, works as follows:

Use every place node of the OSM dataset which has a village-tag (place=village).

Search in a radius of ca. 700 m for a street with one of the following highway-values: residential, unclassified or service.

If no street can be found, mark the place as “unmapped”!

My results for the entire OSM planet can be found under the following webpage.

May 20th, 2016

The reputation of a contributor in OpenStreetMap (OSM) plays a significant role, especially when considering the quality assessment of the collected data. Sometimes it’s difficult to make a meaningful statement about a contributor by simply looking at the raw mapping work represented by the number of created objects or used tags. Therefore, it would be really helpful if we would have some additional information about the person who contributes to the project. For example: Does she/he help other contributors? Is her/his work somehow documented or based on one of the “discussed” proposals? Or does she/he work as a lone warrior in the OSM world?

In 2010 I created “How did you contribute to OpenStreetMap?” (HDYC) as a kind of fun side project. Nowadays many people use it to get some detailed information about OSM contributors. Some of you are probably familiar with the “verified” icon used on some celebrity Twitter accounts. I created a similar new feature for the aforementioned HDYC page. If you connect your related OSM accounts, your profile will be marked as “verified”.

May 1st, 2016

#Hashtags are commonly used on Twitter to find content for a specific topic. Also in the OpenStreetMap (OSM) universe they are popular and utilized to mark changesets, which have been contributed during a special event, such as mapping parties or HOT tasks. However, in most cases, they are added in the changeset comment section. Back in November, 2015, several people discussed the pros and cons about (only) this approach. You can find a general overview of good changeset comments here. The aforementioned wiki page also shows why it is important to write a “concise and adequate“ description of the edit. Anyway, I also support the opinion that we should not generalize this statement and only add hashtags in our changeset comments. I prefer the different approach in which the contributor adds an extra changeset tag for the hashtag(s). For example, the widely used JOSM editor allows optional tags (as you can see here). On the other hand, the iD editor, which is used in many cases by new contributors, doesn’t offer this feature. However, I am sure that with some minor changes this could be fixed. A more or less complete set of recommended or mandatory changeset tags can be found here.

January 20th, 2016

Since its rise in popularity, the well-known online encyclopedia Wikipedia has been struggling with manipulation or, in the worst-case, vandalism attempts. Similarly, the OpenStreetMap (OSM) project suffered several times over the past few years of cases where incorrect map data edits were made. These erroneous edits can stem at times from (new) contributors or illegal data imports (or automated edits) which have not been discussed in advance with the community or the Data Working Group (DWG) and corrupted existing project data. The current OSM wiki page gives a great overview about general guidelines and e.g. types of vandalism. Another page in the wiki also mentions a prototype of a rule based system for the automatic detection of vandalism in OSM, which I developed in 2012. However, the system has never actually been implemented. Today, the contributors of OSM can use a variety of different tools to inspect an area or particular map changes. A few of them are listed below (complete list can be found here):

August 10th, 2015

Almost one year has passed again. This means it’s time for the fourth OpenStreetMap (OSM) member activity analysis. The previous editions are online here: 2014, 2013 and 2012. Simon Poole already posted some interesting stats about the past few years. You can find all his results on the OSM wiki page. However, similar to last year, I try to dig a little deeper in some aspects.

Overall the OSM project has officially more than 2.2 million registered members (Aug, 9th 2015). For several of my OSM related webpages I create a personal OSM contributor database, based on the official OSM API v0.6. Anyway, when using this API, the final table will show a list with more than 3 million individual OSM accounts (Aug, 9th 2015). I’m not sure what the cause for this gap of almost 1 million members between the official number and the member number extracted with the API could be. Maybe some of you have a possible explanation? However, I think many accounts are created by spammers or bots.

April 17th, 2015

OSMstats contains several statistics about the OpenStreetMap (OSM) project, such as daily-created objects, the amount of active contributors or detailed numbers for individual countries. One way to determine the sum of created or modified Node objects, is to use the minutely, hourly or daily OSM replication change files and counting the values for each country of the world. Sadly, this approach has some drawbacks. Firstly, the official files do not contain, for example, all Nodes of a modified way, which is required, when trying to find the country where the change took place. Furthermore, the determination of the country for a specific OSM object really depends on the border’s level of detail: More detailed country borders make the processing quite time-consuming. Some of you probably experienced this problem before when using Osmosis or a different OSM processing tool. Anyway, for calculating additional country statistics I tried a new approach:

March 24th, 2015

The first book about the OpenStreetMap (OSM) project was written by Frederik Ramm and Jochen Topf, two well-known OSM enthusiasts, in 2008. The first version was in German which was later translated into an improved English version. It contains similar information as can be found in the book by Jonathan Bennett, which was published in 2010, detailing how the projects’ geodata is collected, which editors can be used, some explanations about tags, key and values and how the rendering stack works. Both books are great resources to learn about the OSM basics and to get an overview about useful software.

January 18th, 2015

The Missing Maps project is a collaboration between the Humanitarian OpenStreetMap Team (HOT) and various partner agencies, such as the American or the British Red Cross. One of their main objectives is “to map the most vulnerable places in the developing world, in order that international and local NGOs and individuals can use the maps and data to better respond to crises affecting the areas.” You can find additional information about the Missing Maps Project on the OpenStreetMap (OSM) wiki and their project page.

A year ago, I created a webpage where you can filter OSM changesets by a specific comment. Sadly the webpage provides only a search for the latest seven days. However, the Missing Maps project asked me, if it’s possible to “look over a longer time scale”? Here we go, based on a similar concept that I used for a webpage that I created for the HOT Ebola Response, I made a Map that displays all OSM changesets which have the hashtag #MissingMaps in the comment attribute and have been created since August 1st, 2014. It’s online here and being updated on an hourly basis: http://resultmaps.neis-one.org/osm-missingmaps

November 2nd, 2014

For almost eight months the OpenStreetMap (OSM) community has been collecting geo information for the West Africa Ebola outbreak response now. The collective work of the crowd is somewhat managed by the Humanitarian OpenStreetMap Team (HOT). For example, the Task Manager provided by HOT gives interested contributors information in which areas map features are needed. However, you can find additional information in an article by Pierre Beland, which he wrote during a conference where he presented the efforts of the OSM community. The OSM wiki contains some useful information about the West Africa Ebola Response too. Matt Irwin also wrote a summary about the OSM mapper contributions and created an interesting visualization of all the mapping work.

September 14th, 2014

Gregory Marler had the great idea to implement an “explored” map, based on a concept that some of you might know as “fog of war” from strategy video games. So here you go: I extended my OSM Heat Map with the “Explored Map Style”. It essentially reveals the contribution areas of an OpenStreetMap member in a “fog of war” style. The following figure shows Gregory’s amazing “explored” OSM map.

The Heat & Explored Maps are available for almost all OSM members who contributed at least several changesets here: http://yosmhm.neis-one.org (The new “Explored Map Style” can be selected in the layer panel (upper right corner). Additionally, I added the awesome looking and well known Watercolor and Toner map styles from Stamen design)